Seat back hinge-latch



Sept. 19, 1967 R, c. BENcx-:NE

SEAT BACK HINGE-LATCH Filed June 30, 1966 R. O T V N l Sept. 19, 1967 R.C. BENCENE SEAT BACK HINGE-LATCH 2 Sheetsheef;

Filed June 30, 1966 INVENTOR.

M Ww www@ O C. T m M E www RM mi@ m nw United States Patent Oiiice3,342,527 Patented Sept. 19, 1967 3,342,527 SEAT BACK HINGE-LATCH RobertC. Bencene, Jamestown, N .Y., assignor to Weber- Knapp Company,Jamestown, N.Y. Filed June 30, 1966, Ser. No. 561,818 4 Claims. (Cl.297-379) ABSTRACT OF THE DISCLOSURE A positionally adjustable hingestructure for seats in which a latch |bar and a cooperable abutmentmember are disposed in offset relationship to the hinge axis, the latchbar being provided with `recesses so shaped as to require the seat backto be pulled forwardly before the latch bar may be released manuallyfrom the abutment member and wherein the latch bar and abutment memberare fully enclosed by the hinge construction.

This invention relates to seating devices having angularly adjustablebacks; such as chairs which are useful for example in boats, airplanes,railway coaches, buses trucks, or other vehicles or the like; whereverit is desirable to provide a seating unit having a pivoted back which isadjustable to different angular positions relative t-o the vertical.More particularly, the invention relates to improvements in such seatingarrangements whereby to increase assurances against accidental lreleaseof the chair-back holding mechanism.

Generally stated, it is a principal object of this invention to providein a chair as aforesaid an improved chairback hinge support andposition-holding latch mechanism.

More specifically, it is an object of the invention to provide in anadjust-able chair as aforesaid an improved latch-mechanism which is notprone to accidental release, and which is therefore especially desirablefor use lfor example in airplanes, railway coaches, automobile buses,boats or the like; or wherever persons are apt to accidentally brushagainst the control latch device.

Another object is to provide an improved combination hinge and latchdevice as aforesaid which obviates the possibility of injuriousengagements of the hand of the chair operator between relatively movingparts of the mechanism.

Still another object is to provide an improved chairhinge and latcharrangement as aforesaid which is con-` venient and easy of operation,so that the occupant may with utmost ease and facility adjust the chairto the desired, partly or fully reclining, or upright position.

A further object is to provide an improved chair-back control device asaforesaid comprising only a few simple and inexpensively made ybutdurable parts, which may be assembled at a minimum expenditure of timeand labor.

Other objects and advantages of the invention will appear hereinafterfrom the following specification and the accompanying drawing, in which:

FIG. 1 is a side elevational view of a chair-back hinge and latch device`of the invention; the chair back being disposed in substantiallyvertical position;

FIG. 2 corresponds to FIG. 1 but shows the mechanism in partly recliningposition, and by broken lines in fully reclining position;

FIG. 3 is a fragmentary vertical sectional view through a chairconstruction embodying a device of the invention; the latter being shownby way of an inside elevational view thereof; the seat being in uprightposition;

FIG. 4 is a front elevational view of a device of the invention;

FIG. 5 is a sectional view taken as suggested by line 5 5 of FIG. 4;

FIG. 6 is a view corresponding to FIG. 5 Ibut showing the mechanism whent-he seat back is in an intermediate reclining position;

FIG. 7 corresponds to FIG. 6 but shows the mechanism when the seat backis in fully reclined position;

FIG. 8 is a fragmentary sectional view taken as suggested by line 8-8 ofFIG. 3; and

FIG. 9 is a fragmentary view of the latch bar and locking pinarrangement illustrating how the device automatically guards againstforward collapse of the seat back under sudden stop or decelerationconditions.

As shown by way of example herein the invention is illustrated as beingembodied in a chair construction comprising a seat frame member 10mounting a seat cushion 12, and a back rest frame member 14 carrying acushion 16. The back rest frame 14 is hingedly mounted relative to theseat frame 10l -by means of a pair of combination hinge-latch units ofthe invention which are designated generally at 20; said units beingdisposed at opposite sides of the chair construction. Thus, it will beunderstood that although the units 2020 are functionally identical andcomprise structurally similar parts, each pair of units twill comprise aright hand and a left hand unit, respectively.

As shown in the drawing herewith each unit comprises a lower hinge-blade member 22; an upper hinge blade member 24 pivotally connected tothe member 22 by means of a hinge pin 25; and a hinge control latch bar26. The latch bar 26 is pivotally mounted -as by means of a pin 28 tothe upper hinge blade 24. At its lower end the latch 26 is formed with aseries of dwells as indicated at 29, 29 for selective engagement with alock pin 30. At its upper end the latch bar 26 is formed with alaterally extending manual control linger portion 32. Whereas in thedrawing herewith the latch member is illustrated to comprise a pair ofinterdigitated arm members, it will be appreciated that the latch bardevice may comprise ra single rocker arm, and that the two piececonstruction as shown herein is provided only to facilitate manufactureof the parts. The latch member is at all times spring-biased to rotatein clockwise direction as viewed in FIGS. 3-7 by means of a torsionspring 35. Thus it will be appreciated that the parts will bedimensioned and relatively arranged so that the latch device willautomatically tend to engage the lock pin 30 to hold the chair back inits intended angularly adjusted position. The hinge blades 22, 24 areformed with lright angle flange portions 38, thereby lfacilitating theirattachments as by means of bolts 39 to cooperating flange portions 40 ofthe seat and back structures 10, 14, respectively.

To guard against inadvertent engagements of the chair operators lingersbetween relatively moving parts of the chair hinge and/or latchmechanism, a pair of guard plates as indicated generally at 42, 44, areprovided to cover the latch mechanism as well as the operative gapbetween the hinge blades 22, 24. Thus, the lower guard plate 42 isshaped as best shown in FIGS. 1, 2, 5, 6, 7, to comprise a generallysmooth and flat outside plate portion 46 bounded by top and bottomflange portions 47, 48; and the upper guard plate 44 similarly comprisesa side plate portion 50 bounded by ange portions 51, 52. Each guardplate is suitably perforated so as to accommodate the main hinge pin 25therethrough aswell as the latch pivot and lock pin members 28, 30,respectively; thus mounting the guard plates relative to thecorresponding hinge blades. The guard plates are further attached to thecorresponding hinge blades as by means of rivets illustrated at 54. Theupper guard plate 44 is arcuately slotted as indicated at 56 toaccommodate the laterally extending arm portion of the control member 32in freely movable relation therein.

It is a particular feature of the present invention that, as shown inFIG. 9, the dwell portions 29, 29 of the latch member 26 each includes ahook portion 60 which is `so shaped as to provide a socket therebehindwhich naturally cradles against the latch pin 30, thereby guardingagainst any unintended dislodgment of the latch mechanism. Hence,whenever the latch bar 26 is thusly hooked on the lock pin 30, as shownfor example at FIGS. 3, 5, 6, 9, any backward pressure against thecontrol finger portion 32 will be effectively resisted by the aforesaidcradled engagement of the latch bar on the lock pin and the latchmechanism will not release. It is therefore prerequisite to rst swingthe seat back unit 14-16 forwardly (regardless of whatever attitude itmay be locked in) before the latch bar may be freed from the lock pin 30by means of manual pressures applied against the control member 32.

In consequence, it is impossible for the latch mechanism to beinadvertently tripped open, such as by accidentally brushing against thecontrol member 32, because the seat back unit must rst be pulledupwardly and forwardly in order to permit the latch mechanism to bereleased. This feature of the mechanism of the invention is of courseparticularly advantageous when employed in connection with seatingdevices used in speed boats, buses, airplanes or the like, and whereversubstantial motion accelerations are encountered and/or whenever thechair is being used in close quarters and where people are moving about.

FIG. 9 illustrates how the hinge-latch mechanism of the inventionautomatically guards against forward collapse of the seat back such asupon vehicle sudden stop or deceleration conditions. As explainedhereinabove, it is essential that provision be made for pulling the seatback slightly forwardly from its upstanding locked position, in order toenable the operator to release the latch mechanism by pressing manuallyagainst the handle 32. Therefore, the seat back must be at all timesfree to move slightly forwardly, when standing in any upright lockedattitude. However, it is also essential to the safety of the occupantthat in event of a sudden stop or deceleration of the vehicle in whichthe seat is mounted, that the seat back be positively prevented fromcollapsing forwardly with injurious results to the occupant.

The safeguard against such collapse in the case of the present inventionis provided by the positional and operative relationships of the latchbar 26 and the main hinge pin 25. The pin 25 is dimensioned to projectendwise into the path of the latch bar 26 and to stop it from anymovement further forwardly than shown by the broken line illustration ofthe latch bar in FIG. 9. Thus, it will be clearly seen that whenever theseat back tends to fall forwardly beyond the position corresponding tothe broken line showing of the hinge parts, the mid por tion of thelatch bar 26 will abut against the extending end of the hinge pin 25.The upper end of the latch bar is pivotally carried by the pin 28 andthe lower end of the latch bar is spring-pressed into securely hookedposition against the lock pin 30; thereby positively preventing anyfurther forward movement of the seat back.

Therefore, it will be appreciated that the combination hinge and latchmechanism of the invention provides a structurally simple and ruggeddevice which provides the chair-occupant with facility to easily adjustthe inclination of the Ichair back at any time, while operating at alltimes automatically to safeguard the occupant against accident such asmight otherwise occur upon accidental release of the latch or forwardcollapse of the chair back. Also, it will of course be appreciated thatwhereas only one form of the invention has been illustrated by way ofexample and described in detail hereinabove, various changes may be madetherein without departing from the spirit of the invention or the scopeof the following claims.

I claim:

1. A combination seat back hinge and latch mechanism comprising,

a pair of hinge blades adapted to be mounted respectively on a chairseat frame and a chair back frame, hinge means pivotally interconnectingsaid hinge blades for relative rotation about a rst axis,

a lock abutment extending from one of said blades in spaced relation tosaid first axis,

a latch bar pivotally mounted upon the other of said hinge blades abouta second axis spaced from said rst axis so that relative rotationbetween said hinge blades to lower the back frame moves said second axistoward said abutment, said latch bar being formed with a laterallyextending manual control arm portion and being formed with a pluralityof recesses adapted to receive with said lock abutment therein,

spring means biasing said latch bar to move into engagement with saidlock abutment,

the parts being so dimensioned and relatively arranged that said latchbar is operable to hold the seat back in a selected one of a series ofpredetermined vertically inclined attitudes,

at least one of said recesses being shaped to present a shoulder toengage against and prevent release from said locking abutment unless theseat back is pulled forwardly prior to manual adjustment of said controlarm.

2. A mechanism as set forth in claim 1 wherein said mechanism includesstop means limiting movements of said latch bar when the seat back tendsto move forwardly of a vertically upstanding attitude, therebyV lockingthe `seat back against forward collapsing movement.

3. A mechanism as set forth in claim 2 wherein said mechanism includescover plate means conforming generally to the contours of said hingeblades and xed respectively thereto, thereby enclosing said latch barand covering the scissors gap between said hinge blades.

4. A mechanism as set forth in claim 1 wherein said hinge meanscomprises a pin-like element having an end portion extending beyond saidhinge blades and into interfering relation with said latch bar when saidseat back tends to move forwardly beyond a vertically upstandingattitude.

References Cited UNITED STATES PATENTS 2,912,045 11/1959 Milly 297-3632,959,206 11/1960 Tedesco 297-367 r3,008,765 11/1961 Tischler et al297-367 3,051,526 8/1962 Werner et -al 297-367 3,079,199 2/1963 Tischler297-367 3,232,136 2/1966 Bahmoller 297-366 X DAVID J. WILLIAMOWSKY,Primary Examiner.

FRANK B. SHERRY, Examiner.

G. O. FINCH, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N0 3 ,342,527 September 19 1967 Robert C. Bencene It is hereby certified thaterror appears in the above numbered paterltl requiring correction andthat the said Letters Patent should read as corrected below.

Column 4 line 25 strike out "with" Signed and sealed this 15th day ofOctober 1968.

(SEAL) Attest:

EDWARD J. BRENNER Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer

1. A COMBINATION SEAT BACK HINGE AND LATCH MECHANISM COMPRISING, A PAIROF HINGE BLADES ADAPTED TO BE MOUNTED RESPECTIVELY ON A CHAIR SEAT FRAMEAND A CHAIR BACK FRAME, HINGE MEANS PIVOTALLY INTERCONNECTING SAID HINGEBLADES FOR RELATIVE ROTATION ABOUT A FIRST AXIS, A LOCK ABUTMENTEXTENDING FROM ONE OF SAID BLADES IN SPACED RELATION TO SAID FIRST AXIS,A LATCH BAR PIVOTALLY MOUNTED UPON THE OTHER OF SAID HINGE BLADES ABOUTA SECOND AXIS SPACED FROM SAID FIRST AXIS SO THAT RELATIVE ROTATIONBETWEEN SAID HINGE BLADES TO LOWER THE BACK FRAME MOVES SAID SECOND AXISTOWARD SAID ABUTMENT, SAID LATCH BAR BEING FORMED WITH A LATERALLYEXTENDING MANUAL CONTROL ARM PORTION AND BEING FORMED WITH A PLURALITYOF RECESSES ADAPTED TO RECEIVE WITH SAID LOCK ABUTMENT THEREIN, SPRINGMEANS BIASING SAID LATCH BAR TO MOVE INTO ENGAGEMENT WITH SAID LOCKABUTMENT, THE PARTS BEING SO DIMENSIONED AND RELATIVELY ARRANGED THATSAID LATCH BAR IS OPERABLE TO HOLD THE SEAT BACK IN A SELECTED ONE OF ASERIES OF PREDETERMINED VERTICALLY INCLINED ATTITUDES, AT LEAST ONE OFSAID RECESSES BEING SHAPED TO PRESENT A SHOULDER TO ENGAGE AGAINST ANDPREVENT RELEASE FROM